Methods of voice enhancement strive to either reduce listener fatigue by minimizing the effects of noise or increasing the intelligibility of the recorded voice signal. However, quantification of voice enhancement has been a difficult and often subjective task. The final arbiter has been human, and various listening tests have been devised to capture the relative merits of enhanced voice signals. Therefore, there is a need for a method of quantifying an enhancement made to a voice signal. The present invention is such a method.
U.S. Pat. Appl. No. 20010014855, entitled “METHOD AND SYSTEM FOR MEASUREMENT OF SPEECH DISTORTION FROM SAMPLES OF TELEPHONIC VOICE SIGNALS,” discloses a device for and method of measuring speech distortion in a telephone voice signal by calculating and analyzing first and second discrete derivatives in the voice waveform that would not have been made by human articulation, looking at the distribution of the signals and the number of times the signals crossed a predetermined threshold, and determining the number of times the first derivative data is less than a predetermined value. The present invention does not measure speech distortion as does U.S. Pat. Appl. No. 20010014855. U.S. Pat. Appl. No. 20010014855 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. Appl. No. 20020167937, entitled “EMBEDDING SAMPLE VOICE FILES IN VOICE OVER IP (VoIP) GATEWAYS FOR VOICE QUALITY MEASUREMENTS,” discloses a method of measuring voice quality by using the Perceptual Analysis Measurement System (PAMS) and the Perceptual Speech Quality Measurement (PSQM). The present invention does not use PAMS or PSQM as does U.S. Pat. Appl. No. 20020167937. U.S. Pat. Appl. No. 20020167937 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. Appl. No. 20040059572, entitled “APPARATUS AND METHOD FOR QUANTITATIVE MEASUREMENT OF VOICE QUALITY IN PACKET NETWORK ENVIRONMENTS,” discloses a device for and method of measuring voice quality by introducing noise into the voice signal, performing speech recognition on the signal containing noise. More noise is added to the signal until the signal is no longer recognized. The point at which the signal is no longer recognized is a measure of the suitability of the transmission channel. The present invention does not introduce noise into a voice signal as does U.S. Pat. Appl. No. 20040059572. U.S. Pat. Appl. No. 20040059572 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. Appl. No. 20040167774, entitled “AUDIO-BASED METHOD SYSTEM, AND APPARATUS FOR MEASUREMENT OF VOICE QUALITY,” discloses a device for and method of measuring voice quality by processing a voice signal using an auditory model to calculate voice characteristics such as roughness, hoarseness, strain, changes in pitch, and changes in loudness. The present invention does not measure voice quality as does U.S. Pat. Appl. No. 20040167774. U.S. Pat. Appl. No. 20040167774 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. Appl. No. 20040186716, entitled “MAPPING OBJECTIVE VOICE QUALITY METRICS TO A MOS DOMAIN FOR FIELD MEASUREMENTS,” discloses a device for and method of measuring voice quality by using the Perceptual Evaluation of Speech Quality (PESQ) method. The present invention does not use the PESQ method as does U.S. Pat. Appl. No. 20040186716. U.S. Pat. Appl. No. 20040186716 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. Appl. No. 20060093094, entitled “AUTOMATIC MEASUREMENT AND ANNOUNCEMENT VOICE QUALITY TESTING SYSTEM,” discloses a device for and method of measuring voice quality by using the PESQ method, the Mean Opinion Score (MOS-LQO) method, and the R-Factor method described in International Telecommunications Union (ITU) Recommendation G.107. The present invention does not use the PESQ method, the MOS-LQO method, or the R-factor method as does U.S. Pat. Appl. No. 20060093094. U.S. Pat. Appl. No. 20060093094 is hereby incorporated by reference into the specification of the present invention.